期刊文献+
共找到2,284篇文章
< 1 2 115 >
每页显示 20 50 100
Promoting Environmental Risk Assessment and Control of Emerging Contaminants in China
1
作者 Bin Wang Qian Sui +2 位作者 Huijuan Liu Gang Yu Jiuhui Qu 《Engineering》 SCIE EI CAS CSCD 2024年第6期13-17,共5页
1.Introduction In recent years,China has carried out an extensive preventative battle against air,water,and soil pollution,and the nation’s environmental quality-as reflected by conventional pollutant indicators—has... 1.Introduction In recent years,China has carried out an extensive preventative battle against air,water,and soil pollution,and the nation’s environmental quality-as reflected by conventional pollutant indicators—has significantly improved.At the same time,the issue of emerging contaminants(ECs)is beginning to receive increasing attention.ECs generally refer to newly discovered or noticeable pollutants that pose risks to the ecological environment or human health.Either they have not been included in environmental management,or existing management measures are insufficient to effectively prevent and control their risks.The ECs of greatest concern generally include persistent organic pollutants(POPs),endocrine-disrupting chemicals(EDCs),pharmaceuticals and personal care products(PPCPs),and microplastics.These four categories of ECs are not entirely separate,as they interrelate with each other(Fig.1).Chemical production and product usage are the main sources of ECs.China is the world’s largest producer and consumer of bulk chemicals,and the production value of China’s chemical industry is predicted to reach 50%of the global total by 2030[1].Scientific control of ECs based on their environmental risk assessment is a necessary way to support the prevention and legal governance of ECs. 展开更多
关键词 LEGAL entirely PREVENTION
下载PDF
Investigation of oxy-fuel combustion for methane and acid gas in a diffusion flame
2
作者 Songling Guo Xun Tao +5 位作者 Fan Zhou Mengyan Yu Yufan Wu Yunfei Gao Lu Ding Fuchen Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第1期106-116,共11页
Co-combustion of methane(CH4)and acid gas(AG)is required to sustain the temperature in Claus reaction furnace.In this study,oxy-fuel combustion of methane and acid gas has been experimentally studied in a diffusion fl... Co-combustion of methane(CH4)and acid gas(AG)is required to sustain the temperature in Claus reaction furnace.In this study,oxy-fuel combustion of methane and acid gas has been experimentally studied in a diffusion flame.Three equivalence ratios(ER=1.0,1.5,2.0)and CH_(4)-addition ratios(CH_(4)/AG=0.3,0.5,0.7)were examined and the flame was interpreted by analyzing the distributions of the temperature and species concentration along central axial.CH_(4)-AG diffusion flame could be classified into three sections namely initial reaction,oxidation and complex reaction sections.Competitive oxidation of CH_(4)and H_(2)S was noted in the first section wherein H_(2)S was preferred and both were mainly proceeding decomposition and partial oxidation.SO_(2)was formed at oxidation section together with obvious presence of H2 and CO.However,H2 and CO were inclined to be sustained under fuel rich condition in the complex reaction section.Reducing ER and increasing CH4/AG contributed to higher temperature,H_(2)S and CH_(4)oxidation and CO_(2)reactivity.Hence a growing trend for CH_(4)and AG to convert into H_(2),CO and SO_(2)could be witnessed.And this factor enhanced the generation of CS2 and COS in the flame inner core by interactions of CH4 and CO_(2)with sulfur species.COS was formed through the interactions of CO and CO_(2)with sulfur species.The CS_(2)production directly relied on reaction of CH_(4)with sulfur species.The concentration of COS was greater than CS_(2)since CS_(2)was probably inhibited due to the presence of H_(2).COS and CS_(2)could be consumed by further oxidation or other complex reactions. 展开更多
关键词 Acid gas METHANE Oxy-fuel combustion OXIDATION Chemical analysis Carbon sulfides
下载PDF
Effect of carbon material and surfactant on ink property and resulting surface cracks of fuel-cell microporous layers
3
作者 Zhekun Chen Weitong Pan +2 位作者 Longfei Tang Xueli Chen Fuchen Wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第5期1-12,共12页
Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(MPL). The first thing is t... Ensuring the consistency of electrode structure in proton-exchange-membrane fuel cells is highly desired yet challenging because of wide-existing and unguided cracks in the microporous layer(MPL). The first thing is to evaluate the homogeneity of MPL with cracks quantitatively. This paper proposes the homogeneity index of a full-scale MPL with an area of 50 cm~2, which is yet to be reported in the literature to our knowledge. Besides, the effects of the carbon material and surfactant on the ink and resulting MPL structure have been studied. The ink with a high network development degree produces an MPL with low crack density, but the ink with high PDI produces an MPL with low crack homogeneity. The polarity of the surfactant and the non-polarity of polytetrafluoroethylene(PTFE) are not mutually soluble,resulting in the heterogeneous PTFE distribution. The findings of this study provide guidelines for MPL fabrication. 展开更多
关键词 Proton-exchange-membrane fuel cell Microporous layer Crack density Crack homogeneity Polytetrafluoroethylene distribution SURFACTANT
下载PDF
Effect of internal structure of a batch-processing wet-etch reactor on fluid flow and heat transfer
4
作者 Qinghang Deng Junqi Weng +2 位作者 Lei Zhou Guanghua Ye Xinggui Zhou 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期177-186,共10页
Batch-processing wet-etch reactors are the key equipment widely used in chip fabrication,and their performance is largely affected by the internal structure.This work develops a three-dimensional computational fluid d... Batch-processing wet-etch reactors are the key equipment widely used in chip fabrication,and their performance is largely affected by the internal structure.This work develops a three-dimensional computational fluid dynamics(CFD)model considering heat generation of wet-etching reactions to investigate the fluid flow and heat transfer in the wet-etch reactor.The backflow is observed below and above the wafer region,as the flow resistance in this region is high.The temperature on the upper part of a wafer is higher due to the accumulation of reaction heat,and the average temperature of the side wafer is highest as its convective heat transfer is weakest.Narrowing the gap between wafer and reactor wall can force the etchant to flow in the wafer region and then facilitate the convective heat transfer,leading to better within-wafer and wafer-to-wafer etch uniformities.An inlet angle of 60°balances fluid by-pass and mechanical energy loss,and it yields the best temperature and etch uniformities.The batch with 25wafers has much wider flow channels and much lower flow resistance compared with that with 50wafers,and thus it shows better temperature and etch uniformities.These results and the CFD model should serve to guide the optimal design of batch-processing wet-etch reactors. 展开更多
关键词 Wet-etch reactor Batch-processing Computational fluid dynamics Reaction heat Internal structure Etch uniformity
下载PDF
Effect of samarium doping on the activity and sulfur resistance of Ce/MnFeO_(x) catalyst for low-temperature selective catalytic reduction of NO_(x) by ammonia
5
作者 Qiyao Zhang Shuangshuang Zhang +1 位作者 Xu Hu Yongmin Huang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第7期272-282,共11页
The self-made MnFeO_(x) catalysts doped with cerium and samarium were prepared by impregnation method for low-temperature selective catalytic reduction(SCR)by NH3.In this work,the surface properties of the series of M... The self-made MnFeO_(x) catalysts doped with cerium and samarium were prepared by impregnation method for low-temperature selective catalytic reduction(SCR)by NH3.In this work,the surface properties of the series of MnFe-based catalysts were studied.The results indicate Sm-modified catalyst have superior low-temperature SCR activity;NO_(x) conversion maintained at nearby to 100%at 90℃ to 240℃.In addition,The N_(2) selectivity of Sm doping remains above 80%in the range of 60℃ to 150℃.In SO_(2) poisoning test,the NO_(x) conversion can be remained>90%after 10 h of reaction.The XPS,NH_(3)-TPD and H_(2)-TPR results show the catalyst with Sm doping enhances the acid sites and oxidation catalytic sites of mixed oxides serves for improving oxygen vacancies and transfer electrons.In situ diffuse reflaxions infrared Fourier transformations spectroscopy(DRIFTS)results show that NO_(x) is more easily adsorbed on the surface after Sm doping,which provided favorable conditions for the NH_(3)-SCR reaction to proceed.The reaction at the catalyst surface will follow the L-H reaction mechanism by transient reaction test. 展开更多
关键词 SCR Sm doping CATALYST Sulfur resistance In situ DRIFTS SELECTIVITY
下载PDF
Experimental and numerical investigations on micromixing performance of multi-orifice cross-flow jet mixers
6
作者 Hang Yang Zhaojin Lu +4 位作者 Likun Ma Wei Yin Bingjie Wang Zhishan Bai Xiaoyong Yang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第6期63-72,共10页
Multi-orifice cross-flow jet mixers(MOCJMs)are used in various industrial applications due to their excellent mixing efficiency,but few studies have focused on the micromixing performance of MOCJMs.Herein,the flow cha... Multi-orifice cross-flow jet mixers(MOCJMs)are used in various industrial applications due to their excellent mixing efficiency,but few studies have focused on the micromixing performance of MOCJMs.Herein,the flow characteristics and micromixing performance inside the MOCJM were investigated using experiments and computational fluid dynamics(CFD)simulations based on the Villermaux/Dushman system and the finite-rate/modified eddy-dissipation model.The optimal A value was correlated with the characteristic parameters of MOCJMs to develop a CFD calculation method applicable to the study of the micromixing performance of the MOCJMs.Then the micromixing efficiency was evaluated using the segregation index XS,and the effects of operational and geometric parameters such as mixing flow Reynolds number(ReM),flow ratio(RF),total jet area(ST),the number of jet orifices(n),and outlet configuration on the micromixing efficiency were investigated.It was found that the intensive turbulent region generated by interactions between jets,as well as between jets and crossflows,facilitated rapid reactions.XS decreased with increasing ReM and decreasing RF.Furthermore,MOCJMs with lower ST,four jet orifices,and the narrower outlet configuration demonstrated a better micromixing efficiency.This study contributes to a deeper understanding of the micromixing performance of MOCJMs and provides valuable guidance for their design,optimization,and industrial application. 展开更多
关键词 Multi-orifice cross-flow jet mixer Micromixing performance Finite-rate/modified eddy dissipation model Computational fluid dynamics Villermaux/Dushman reaction
下载PDF
Evaluating two stages of silicone-containing arylene resin oxidation via experiment and molecular simulation
7
作者 Jiangtao Cai Qingfu Huang +4 位作者 Huan Chen Tao Zhang Bo Niu Yayun Zhang Donghui Long 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第2期189-202,共14页
Silicon-containing aryl acetylene resin(PSA)is a new type of high-temperature resistant resin with excellent oxidation resistance,whereas antioxidant reaction mechanism of PSA resin under ultra-high temperatures still... Silicon-containing aryl acetylene resin(PSA)is a new type of high-temperature resistant resin with excellent oxidation resistance,whereas antioxidant reaction mechanism of PSA resin under ultra-high temperatures still remains unclear.Herein,the oxidation behavior and mechanisms of PSA resin are systematically investigated combining kinetic analysis and Reax FF molecular dynamics(MD)simulations.Thermogravimetric analysis indicates that the oxidation process of PSA resin undergoes two main steps:oxidative mass gain and oxidative degradation.The distributed activation energy model(DAEM)is employed for describing oxidation processes and the best-fit one is obtained using genetic algorithms and differential evolution.DAEM model demonstrates that the oxidative weight gain stage is dominated by two virtual reactants and the oxidative degradation stage consists of three virtual reactants.Correspondingly,the observation of MD reaction pathways indicates that oxygen oxidation of unsaturated structures occurs in the initial stage,which results in the formation of PSA resin oxides.Furthermore,cracked pieces react with O_(2)to generate CO and other chemicals in the second step.The resin matrix's great antioxidation resilience is illustrated by the formation of SiO_(2).The analysis based on MD simulations exhibits an efficient computational proof with the experiments and DAEM methods.Based on the results,a two-stage reaction mechanism is proposed,which provides important theoretical support for the subsequent study of the oxidation behavior of silica-based resins. 展开更多
关键词 PSA resin Oxidative degradation Thermogravimetric analysis DAEM reaction kinetics ReaxFF simulation
下载PDF
Agglomeration of coal and polyethylene mixtures during fixed‑bed co‑gasification
8
作者 Igor G.Donskoy Aleksandr N.Kozlov +2 位作者 Maksim V.Penzik Denis A.Svishchev Lu Ding 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第2期91-100,共10页
The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene(up to 20 wt%fraction)in a laboratory reactor.The work aims to study the agglomeration process dur... The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene(up to 20 wt%fraction)in a laboratory reactor.The work aims to study the agglomeration process during the heating and oxidation of the mixtures.The measurement results(gas composition,pressure drop)provide indirect information on the dynamics of thermal decomposition and structural changes in the fuel bed.We have shown that the interaction between polyethylene and a coal surface leads to the formation of dense agglomerates,in which the molten polymer acts as a binder.Clinkers form as a result of interfacial interactions between components and filtration flow rearranging.The hydrogen/carbon ratio in the solid residue of coal-polyethylene co-gasification increases from 0.07–0.2 to 1.11,indicating the formation of stable hydrocarbon compounds on the carbon surface.The conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to agglomeration in mixtures of coal with polyethylene. 展开更多
关键词 COAL POLYETHYLENE GASIFICATION Combustion AGGLOMERATION
下载PDF
Green Synthesis of Iron(Ⅱ,Ⅲ)-polyphenol Nanoparticles and Their Adsorption of Malachite Green
9
作者 胡玉 ZHOU Fan +5 位作者 ZHANG Nan PAN Xiaobin LI Shiying ZHANG Dong LI Li 张玲帆 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第4期1025-1030,共6页
Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient conditions.The obtained materials were characterized by scanning elec... Three kinds of iron nanoparticles(FeNPs)were prepared via green route based on pomegranate(PG),green tea(GT),and mulberry(ML)extracts under ambient conditions.The obtained materials were characterized by scanning electron microscopy(SEM),transmission electronic microscopy(TEM),X-ray energy-dispersive spectrometer(EDS),X-ray diffraction(XRD),fourier transform infrared spectroscopy(FTIR),and X-ray photoelectron spectroscopy(XPS)techniques.The experimental results show that FeNPs were in the form of amorphous iron(Ⅱ,Ⅲ)-polyphenol complex with different dispersity and morphologies.GT-Fe has the smallest size range of 25-35 nm,PG-Fe has a moderate size-distribution of 30-40 nm,while ML-Fe formed a tuberous net-type with a sheeting structure.PG-Fe displays the highest removal efficiency of 90.2%in 20 min towards cationic dye of malachite green(16.6%by ML-Fe and 69.3%by GT-Fe),which is attributed to its highest polyphenol content,lowest zeta potential,as well as the most Fe^(2+)on the surface of FeNPs.The removal mechanism was mainly induced by electrostatic adsorption based on pH and zeta potential tests. 展开更多
关键词 IRON NANOPARTICLES POMEGRANATE green tea MULBERRY ADSORPTION
下载PDF
Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler
10
作者 Chen Han Youmin Situ +4 位作者 Huaxing Zhu Jianliang Xu Zhenghua Dai Guangsuo Yu Haifeng Liu 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第4期203-215,共13页
Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial gasification.In this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas ... Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial gasification.In this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation method.Considering the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was developed.The modified model shows high accuracy in validation.In computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial data.Compared with Smith's model,the temperature decay along the axial direction calculated by the modified model is faster.Syngas components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC. 展开更多
关键词 Radiant syngas cooler Weighted-sum-of-gray-gases model Numerical simulation Particle radiation
下载PDF
Kinetics insights into size effects of carbon nanotubes'growth and their supported platinum catalysts for 4,6-dinitroresorcinol hydrogenation
11
作者 Yan Zhang Xiangxue Zhang +6 位作者 Keng Sang Wenyao Chen Gang Qian Jing Zhang Xuezhi Duan Xinggui Zhou Weikang Yuan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第8期133-140,共8页
Size effects are a well-documented phenomenon in heterogeneous catalysis,typically attributed to alterations in geometric and electronic properties.In this study,we investigate the influence of catalyst size in the pr... Size effects are a well-documented phenomenon in heterogeneous catalysis,typically attributed to alterations in geometric and electronic properties.In this study,we investigate the influence of catalyst size in the preparation of carbon nanotube(CNT)and the hydrogenation of 4,6-dinitroresorcinol(DNR)using Fe_(2)O_(3)and Pt catalysts,respectively.Various Fe_(2)O_(3)/Al_(2)O_(3)catalysts were synthesized for CNT growth through catalytic chemical vapor deposition.Our findings reveal a significant influence of Fe_(2)O_(3)nanoparticle size on the structure and yield of CNT.Specifically,CNT produced with Fe_(2)O_(3)/Al_(2)O_(3)containing 28%(mass)Fe loading exhibits abundant surface defects,an increased area for metal-particle immobilization,and a high carbon yield.This makes it a promising candidate for DNR hydrogenation.Utilizing this catalyst support,we further investigate the size effects of Pt nanoparticles on DNR hydrogenation.Larger Pt catalysts demonstrate a preference for 4,6-diaminoresorcinol generation at(100)sites,whereas smaller Pt catalysts are more susceptible to electronic properties.The kinetics insights obtained from this study have the potential to pave the way for the development of more efficient catalysts for both CNT synthesis and DNR hydrogenation. 展开更多
关键词 KINETICS Size effects Catalytic hydrogenation Active site
下载PDF
Effect of Steam Treatment on the Catalytic Performance of ZSM-5 in the Co-conversion of Methanol and n-Hexane to Aromatics
12
作者 Wei Shumei Xu Yarong +2 位作者 Yang Fan Zhu Kake Zhu Xuedong 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期73-81,共9页
Steam pretreatment is a widely used method for modifying the acidity and structure of zeolites,thereby enhancing their catalytic properties.This study systematically investigated the effects of steam treatment on ZSM-... Steam pretreatment is a widely used method for modifying the acidity and structure of zeolites,thereby enhancing their catalytic properties.This study systematically investigated the effects of steam treatment on ZSM-5 zeolites at varying treatment temperatures and durations.The structural evolution of the catalysts was monitored using N2 adsorptiondesorption,X-ray diffraction,inductively coupled plasma optical emission spectroscopy,scanning electron microscopy,NH3 temperature-programmed desorption,in situ pyridine infrared spectroscopy,and thermogravimetric analysis.The characterization results revealed that mesopores were introduced into the ZSM-5 zeolite catalysts through dealumination induced using steam treatment at moderate temperatures(400 and 500℃).Moreover,compared with the parent catalyst,the steam-treated catalysts exhibited a lower amount of acid sites and relative crystallinity,while the n(Si)/n(Al)ratio increased.In the co-conversion of methanol and n-hexane in a fixed bed reactor at 400℃and 0.5 MPa(N2 atmosphere),with a weight hourly space velocity of 1 h−1 and a stoichiometric ratio of 1:1(CH3OH to n-hexane),the steam-treated catalysts displayed a prolonged catalyst lifetime.Particularly,the parent zeolite had a lifetime of 96 h,while the catalyst treated at 500℃for 12 h had a lifetime of up to 240 h.Additionally,the steam-treated catalysts maintained stable n-hexane conversion and improved aromatic selectivity.Notably,these treated catalysts exhibited a lower deactivation rate than the parent catalyst,and would be conducive to industrial scale-up production. 展开更多
关键词 steam ZSM-5 zeolites co-conversion AROMATIZATION METHANOL N-HEXANE
下载PDF
Kinetics and Mechanism of Hydration of Acrylic Acid over Ion-exchanged Resin:Experimental Exploration and DFT Calculation
13
作者 Yang Fengjing Luo Nianjun +11 位作者 Chen Yuxiang Liu Chuanlei Wang Hao Gao Weikang Guo Guanchu Jiang Hao Zhao Qiyue Zhou Yousheng Wang Yifan Li Peicheng Shen Benxian Sun Hui 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2024年第3期109-121,共13页
Liquid-phase acrylic acid hydration over solid-phase catalysts is a key reaction for the industrial productionof 3-hydroxypropionic acid. However, the relevant literature primarily focuses on the experimental aspects ... Liquid-phase acrylic acid hydration over solid-phase catalysts is a key reaction for the industrial productionof 3-hydroxypropionic acid. However, the relevant literature primarily focuses on the experimental aspects of catalystscreening and exploring reaction conditions, with few accurate descriptions of the reaction kinetics and determination ofthe reaction mechanism. Here, we combined kinetics experiments and theoretical calculations to elucidate the kinetics andmechanism of acrylic acid hydration on a resin catalyst. The pseudo-homogeneous model, and Langmuir-Hinshelwood-Haugen-Watson and Elie-Riedel (ER) heterogeneous models were used to explain the experimental kinetics data. TheER model can explain the experimental data very well, suggesting strong adsorption of acrylic acid on the surface of theresin catalyst. Furthermore, density functional theory calculations show that the hydration follows a stepwise, rather than aconcerted, reaction pathway. The present study provides theoretical insights into the reaction mechanism and kinetics, fillingthe gap in our understanding of the reaction on a fundamental level. 展开更多
关键词 acrylic acid KINETICS resin catalyst DFT method
下载PDF
Simultaneous Degradation, Dehalogenation, and Detoxification of Halogenated Antibiotics by Carbon Dioxide Radical Anions
14
作者 Yanzhou Ding Xia Yu +8 位作者 Shuguang Lyu Huajun Zhen Wentao Zhao Cheng Peng Jiaxi Wang Yiwen Zhu Chengfei Zhu Lei Zhou Qian Sui 《Engineering》 SCIE EI CAS CSCD 2024年第6期78-86,共9页
Despite the extensive application of advanced oxidation processes(AOPs)in water treatment,the efficiency of AOPs in eliminating various emerging contaminants such as halogenated antibiotics is constrained by a number ... Despite the extensive application of advanced oxidation processes(AOPs)in water treatment,the efficiency of AOPs in eliminating various emerging contaminants such as halogenated antibiotics is constrained by a number of factors.Halogen moieties exhibit strong resistance to oxidative radicals,affecting the dehalogenation and detoxification efficiencies.To address these limitations of AOPs,advanced reduction processes(ARPs)have been proposed.Herein,a novel nucleophilic reductant—namely,the carbon dioxide radical anion(CO_(2)^(·-))—is introduced for the simultaneous degradation,dehalogenation,and detoxification of florfenicol(FF),a typical halogenated antibiotic.The results demonstrate that FF is completely eliminated by CO_(2)^(·-),with approximately 100%of Cland 46%of Freleased after 120 min of treatment.Simultaneous detoxification is observed,which exhibits a linear response to the release of free inorganic halogen ions(R^(2)=0.97,p<0.01).The formation of halogen-free products is the primary reason for the superior detoxification performance of this method,in comparison with conventional hydroxyl-radical-based AOPs.Products identification and density functional theory(DFT)calculations reveal the underlying dehalogenation mechanism,in which the chlorine moiety of FF is more susceptible than other moieties to nucleophilic attack by CO_(2)^(·-).Moreover,CO_(2)^(·-)-based ARPs exhibit superior dehalogenation efficiencies(>75%)in degrading a series of halogenated antibiotics,including chloramphenicol(CAP),thiamphenicol(THA),diclofenac(DLF),triclosan(TCS),and ciprofloxacin(CIP).The system shows high tolerance to the pH of the solution and the presence of natural water constituents,and demonstrates an excellent degradation performance in actual groundwater,indicating the strong application potential of CO_(2)^(·-)-based ARPs in real life.Overall,this study elucidates the feasibility of CO_(2)^(·-)for the simultaneous degradation,dehalogenation,and detoxification of halogenated antibiotics and provides a promising method for their regulation during water or wastewater treatment. 展开更多
关键词 Carbon dioxide radical anions Advanced reduction processes Halogenated antibiotics DEHALOGENATION DETOXIFICATION
下载PDF
New Insights into Microplastic Contamination in Different Types of Leachates: Abundances, Characteristics, and Potential Sources
15
作者 Lei Zhang Wentao Zhao +5 位作者 Liang Zhang Zhenxiao Cai Ruiqi Yan Xia Yu Damià Barceló Qian Sui 《Engineering》 SCIE EI CAS CSCD 2024年第6期62-68,共7页
Municipal solid waste(MSW)is an important destination for abandoned plastics.During the waste disposal process,large plastic debris is broken down into microplastics(MPs)and released into the leachate.However,current ... Municipal solid waste(MSW)is an important destination for abandoned plastics.During the waste disposal process,large plastic debris is broken down into microplastics(MPs)and released into the leachate.However,current research only focuses on landfill leachates,and the occurrence of MPs in other leachates has not been studied.Therefore,herein,the abundance and characteristics of MPs in three types of leachates,namely,landfill leachate,residual waste leachate,and household food waste leachate,were studied,all leachates were collected from the largest waste disposal center in China.The results showed that the average MP abundances in the different types of leachates ranged from(129±54)to(1288±184)MP particles per liter(particlesL1)and the household food waste leachate exhibited the highest MP abundance(p<0.05).Polyethylene(PE)and fragments were the dominant polymer type and shape in MPs,respectively.The characteristic polymer types of MPs in individual leachates were different.Furthermore,the conditional fragmentation model indicated that the landfilling process considerably affected the size distribution of MPs in leachates,leading to a higher percentage(>80%)of small MPs(20–100 lm)in landfill leachates compared to other leachates.To the best of our knowledge,this is the first study discussing the sources of MPs in different leachates,which is important for MP pollution control during MSW disposal. 展开更多
关键词 Microplastics Landfill leachate Residual waste leachate Household food waste leachate Source
下载PDF
A critical review on direct catalytic hydrogasification of coal into CH_(4):catalysis process configurations,evaluations,and prospects
16
作者 Shuai Yan Jun Feng +4 位作者 Shenfu Yuan Zihong Xia Fengshuang Han Xuan Qu Jicheng Bi 《International Journal of Coal Science & Technology》 EI CAS CSCD 2024年第3期51-85,共35页
Coal catalytic hydrogasification(CCHG)is a straightforward approach for producing CH_(4),which shows advantages over the mature coal-to-CH_(4) technologies from the perspectives of CH_(4) yield,thermal efficiency,and ... Coal catalytic hydrogasification(CCHG)is a straightforward approach for producing CH_(4),which shows advantages over the mature coal-to-CH_(4) technologies from the perspectives of CH_(4) yield,thermal efficiency,and CO_(2) emission.The core of CCHG is to make carbon in coal convert into CH_(4) efficiently with a catalyst.In the past decades,intensive research has been devoted to catalytic hydrogasification of model carbon(pitch coke,activated carbon,coal char).However,the chemical process of CCHG is still not well understood because the coal structure is more complicated,and CCHG is a combination of coal catalytic hydropyrolysis and coal char catalytic hydrogasification.This review seeks to shed light on the catalytic process of raw coal during CCHG.The configuration of suitable catalysts,operating conditions,and feedstocks for tailoring CH_(4) formation were identified,and the underlying mechanisms were elucidated.Based on these results,the CCHG process was evaluated,emphasizing pollutant emissions,energy efficiency,and reactor design.Furthermore,the opportunities and strategic approaches for CCHG under the restraint of carbon neutrality were highlighted by considering the penetration of“green”H2,biomass,and CO_(2) into CCHG.Preliminary investigations from our laboratories demonstrated that the integrated CCHG and biomass/CO_(2) hydrogenation process could perform as an emerging pathway for boosting CH_(4) production by consuming fewer fossil fuels,fulfilling the context of green manufacturing.This work not only provides systematic knowledge of CCHG but also helps to guide the efficient hydrogenation of other carbonaceous resources such as biomass,CO_(2),and coal-derived wastes. 展开更多
关键词 Coal gasification Catalytic hydrogasification Methane Pressurized fluidized bed
下载PDF
Effects of Coagulation and Ozonation Pretreatments on Biochemical Treatment of Fluid Catalytic Cracking Wastewater
17
作者 Ibrah Landi Ali Lu Jun 《Journal of Environmental Protection》 2024年第2期156-172,共17页
Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and d... Fluid catalytic cracking (FCC) salty wastewaters, containing quaternary ammonium compounds (QACs), are very difficult to treat by biochemical process. Anoxic/oxic (A/O) biochemical system, based on nitrification and denitrification reactions, was used to assess their possible biodegradation. Because of the negative effects of high salt concentration (3%), heavy metals and toxic organic matter on microorganisms’ activities, some techniques consisting of dilution, coagulation and flocculation, and ozonation pretreatments, were gradually tested to evaluate chemical oxygen demand (COD), ammonia-nitrogen (ammonia-N) and total nitrogen (TN) removal rates. In this process of FCC wastewater, starting with university-domesticated sludge, the ammonia-N and TN removal rates were worst. However, when using domesticated SBR’s sludge and operating with five-fold daily diluted influent (thus reducing salt concentration), the ammonia-N removal reached about 57% while the TN removal rate was less than 37% meaning an amelioration of the nitrification process. However, by reducing the dilution factors, these results were inflected after some days of operation, with ammonia-N removal decreasing and TN barely removed meaning a poor nitrification. Even by reducing heavy metals concentration with coagulation/flocculation process, the results never changed. Thereafter, by using ozonation pre-treatment to degrade the detected organic matter of di-tert-butylphenol and certain isoparaffins, COD, ammonia-N and TN removal rates reached 92%, 62% and 61%, respectively. These results showed that the activities of the microorganisms were increased, thus indicating a net denitrification and nitrification reactions improvement. 展开更多
关键词 Ammonia-N Anoxic and Oxic (A/O) Reactor Coagulation and Sedimentation FCC Wastewater Ozone Total Nitrogen (TN)
下载PDF
The Maximum and Minimum Value of Exponential RandićIndices of Quasi-Tree Graph
18
作者 Lei Qiu Xijie Ruan Yan Zhu 《Journal of Applied Mathematics and Physics》 2024年第5期1804-1818,共15页
The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, whe... The exponential Randić index has important applications in the fields of biology and chemistry. The exponential Randić index of a graph G is defined as the sum of the weights e 1 d( u )d( v ) of all edges uv of G, where d( u ) denotes the degree of a vertex u in G. The paper mainly provides the upper and lower bounds of the exponential Randić index in quasi-tree graphs, and characterizes the extremal graphs when the bounds are achieved. 展开更多
关键词 Exponential Randić Index Quasi-Tree Graph Extremal Value Extremal Graphs
下载PDF
Closed-loop scheduling optimization strategy based on particle swarm optimization with niche technology and soft sensor method of attributes-applied to gasoline blending process
19
作者 Jian Long Kai Deng Renchu He 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2023年第9期43-57,共15页
Gasoline blending scheduling optimization can bring significant economic and efficient benefits to refineries.However,the optimization model is complex and difficult to build,which is a typical mixed integer nonlinear... Gasoline blending scheduling optimization can bring significant economic and efficient benefits to refineries.However,the optimization model is complex and difficult to build,which is a typical mixed integer nonlinear programming(MINLP)problem.Considering the large scale of the MINLP model,in order to improve the efficiency of the solution,the mixed integer linear programming-nonlinear programming(MILP-NLP)strategy is used to solve the problem.This paper uses the linear blending rules plus the blending effect correction to build the gasoline blending model,and a relaxed MILP model is constructed on this basis.The particle swarm optimization algorithm with niche technology(NPSO)is proposed to optimize the solution,and the high-precision soft-sensor method is used to calculate the deviation of gasoline attributes,the blending effect is dynamically corrected to ensure the accuracy of the blending effect and optimization results,thus forming a prediction-verification-reprediction closed-loop scheduling optimization strategy suitable for engineering applications.The optimization result of the MILP model provides a good initial point.By fixing the integer variables to the MILPoptimal value,the approximate MINLP optimal solution can be obtained through a NLP solution.The above solution strategy has been successfully applied to the actual gasoline production case of a refinery(3.5 million tons per year),and the results show that the strategy is effective and feasible.The optimization results based on the closed-loop scheduling optimization strategy have higher reliability.Compared with the standard particle swarm optimization algorithm,NPSO algorithm improves the optimization ability and efficiency to a certain extent,effectively reduces the blending cost while ensuring the convergence speed. 展开更多
关键词 BLEND Optimization algorithm Neural networks Particle swarm optimization Mixed integer programming
下载PDF
The Rise of Women’s Education and the Modernity of East Asia:Focusing on the Education of“Virtuous Wives and Worthy Mothers”in China and Japan
20
作者 HE Wei 《Cultural and Religious Studies》 2022年第9期500-516,共17页
This year marks the 50th anniversary of the normalization of diplomatic relations between China and Japan.Looking back on the past and forward to the future,we realize modernity has become a critical issue that not on... This year marks the 50th anniversary of the normalization of diplomatic relations between China and Japan.Looking back on the past and forward to the future,we realize modernity has become a critical issue that not only China and Japan,but the whole East Asian region should pay attention to.China and Japan are both within the“Circle of Confucius Culture”and are both modern latecomer countries.As they were coerced by western countries to enter the modern age,they shared multiple common features.An exploration of the two countries’respective rising of modern women’s education is an important path to discuss the reconstruction of gender and an important method of the course of the embodiment of east-Asian women into modernization drives.With regards to conclusion,entering the modern age,Chinese and Japanese intellectuals reshaped the female gender in terms of interpersonal relationship,value system,and knowledge structure by advocating the idea of“virtuous wives and worthy mothers”education.In the concept of virtuous wives and worthy mothers in East Asia,the Confucian ethics of“docility and virtue”is the soul,and modern scientific knowledge serves this core value.On the other hand,in the course of localization in China and Japan,this imported concept from the West has encountered a completely different historical fate. 展开更多
关键词 women’s education modernity China JAPAN virtuous wives and worthy mothers
下载PDF
上一页 1 2 115 下一页 到第
使用帮助 返回顶部